Houthi rebel fighters stand guard after a reported air strike on the presidential palace in the Yemeni capital Sanaa on December 5, 2017. Mohammed Huwais / AFP
Houthi rebel fighters stand guard after a reported air strike on the presidential palace in the Yemeni capital Sanaa on December 5, 2017. Mohammed Huwais / AFP

Yemen in flux: the only certainty is there is no certainty